Zvigadziko zvegrafiti zvakaputirwa neSiC zvinowanzo shandiswa kutsigira nekupisa makristaro ega ega mumidziyo yesimbi-organic chemical vapor deposition (MOCVD). Kugadzikana kwekupisa, kufanana kwekupisa uye zvimwe zvinongedzo zvekushanda kweSiC zvakaputirwa negrafiti zvinoita basa guru mukukura kwe epitaxial material, saka ndicho chinhu chikuru cheMOCVD michina.
Mukugadzirwa kwewafer, epitaxial layers dzinovakwazve pane mamwe mawafer substrates kuti zvive nyore kugadzira michina. Midziyo inowanzoburitsa chiedza che LED inofanirwa kugadzirira epitaxial layers dzeGaAs pane silicon substrates; SiC epitaxial layer inorimwa pane conductive SiC substrate yekuvaka michina yakaita seSBD, MOSFET, nezvimwewo, yemagetsi akakwira, magetsi akakwira uye mamwe mashandisirwo esimba; GaN epitaxial layer inovakwa pane semi-insulated SiC substrate kuti iwedzere kuvaka HEMT nezvimwe zvishandiso zveRF applications zvakaita sekutaurirana. Maitiro aya haaparadzaniswi neCVD equipment.
Mumidziyo yeCVD, substrate haigone kuiswa zvakananga pasimbi kana kungoiswa pahwaro hwekuisa epitaxial, nekuti inosanganisira kuyerera kwegasi (kwakatambanuka, kwakamira), tembiricha, kumanikidzwa, kugadziriswa, kubviswa kwezvinosvibisa nezvimwe zvinhu zvine chekuita nepesvedzero. Saka, zvakakosha kushandisa hwaro, wobva waisa substrate padiski, wobva washandisa tekinoroji yeCVD kuisa epitaxial pahwaro, inova SiC coated graphite base (inozivikanwawo setrayi).
Zvigadziko zvegrafiti zvakaputirwa neSiC zvinowanzo shandiswa kutsigira nekupisa makristaro ega ega mumidziyo yesimbi-organic chemical vapor deposition (MOCVD). Kugadzikana kwekupisa, kufanana kwekupisa uye zvimwe zvinongedzo zvekushanda kweSiC zvakaputirwa negrafiti zvinoita basa guru mukukura kwe epitaxial material, saka ndicho chinhu chikuru cheMOCVD michina.
Metal-organic chemical vapor deposition (MOCVD) ndiyo tekinoroji huru yekukura kwemafirimu eGaN mubhuruu reLED. Ine zvakanakira zvekushanda kuri nyore, kukura kunodzorwa uye kuchena kwakanyanya kwemafirimu eGaN. Sechinhu chakakosha mukamuri rekuita reMOCVD, hwaro hwebheyaringi hunoshandiswa pakukura kwemafirimu eGaN hunofanirwa kuve nezvakanakira zvekudzivirira kupisa kwakanyanya, kufambisa kupisa kwakafanana, kugadzikana kwakanaka kwemakemikari, kuramba kupisa kwakasimba, nezvimwewo. Graphite material inogona kusangana nemamiriro ezvinhu ari pamusoro apa.
Sechimwe chezvinhu zvikuru zveMOCVD michina, girafiti base ndiyo inotakura uye inodziisa substrate, iyo inosarudza zvakananga kufanana uye kuchena kwezvinhu zvefirimu, saka hunhu hwayo hunokanganisa zvakananga kugadzirira epitaxial sheet, uye panguva imwe chete, nekuwedzera kwehuwandu hwekushandiswa uye shanduko yemamiriro ekushanda, iri nyore kwazvo kupfeka, iri yezvinhu zvinodyiwa.
Kunyangwe graphite iine thermal conductivity yakanaka uye kugadzikana, ine mukana wakanaka sechikamu chekutanga cheMOCVD michina, asi mukugadzirwa kwayo, graphite inoparadza upfu nekuda kwemagasi anoparadza uye organics esimbi, uye hupenyu hwebasa hwechigadziko chegraphite huchaderedzwa zvakanyanya. Panguva imwe chete, kudonha kweupfu hwegraphite kunokonzera kusvibiswa kwechip.
Kubuda kwetekinoroji yekuputira kunogona kupa hupfu hwepamusoro, kuwedzera kupisa, uye kuenzanisa kugoverwa kwekupisa, iyo yave tekinoroji huru yekugadzirisa dambudziko iri. Graphite base munzvimbo yekushandisa michina yeMOCVD, graphite base surface coating inofanira kusangana nehunhu hunotevera:
(1) Hwaro hwegirafiti hunogona kuputirwa zvizere, uye huwandu hwayo hwakanaka, zvikasadaro hwaro hwegirafiti hunogona kusviba nyore nyore mugasi rinoparadza.
(2) Simba rekubatana nechigadziko chegirafiti rakakwirira kuitira kuti chifukidziro chisadonha nyore nyore mushure mekutenderera kwakawanda kwekupisa kwakanyanya uye kupisa kwakaderera.
(3) Ine kugadzikana kwakanaka kwemakemikari kudzivirira kutadza kwekuputira kana tembiricha yakakwira uye mhepo inoparadza.
SiC ine zvakanakira zvekudzivirira ngura, kufambisa kupisa kwakanyanya, kuramba kupisa kunopisa uye kugadzikana kwemakemikari zvakanyanya, uye inogona kushanda zvakanaka mumhepo yeGaN epitaxial. Pamusoro pezvo, thermal expansion coefficient yeSiC yakasiyana zvishoma neya graphite, saka SiC ndiyo chinhu chinodiwa pakuputira pamusoro pe graphite base.
Parizvino, SiC yakajairika inonyanya kuve ye3C, 4H uye 6H, uye mashandisirwo eSiC emhando dzakasiyana dzekristaro akasiyana. Semuenzaniso, 4H-SiC inogona kugadzira zvishandiso zvine simba guru; 6H-SiC ndiyo yakagadzikana zvakanyanya uye inogona kugadzira zvishandiso zvemagetsi; Nekuda kwechimiro chayo chakafanana neGaN, 3C-SiC inogona kushandiswa kugadzira GaN epitaxial layer uye kugadzira zvishandiso zveSiC-GaN RF. 3C-SiC inozivikanwawo seβ-SiC, uye kushandiswa kwakakosha kweβ-SiC ndeyefirimu uye zvinhu zvekuputira, saka β-SiC parizvino ndiyo chinhu chikuru chekuputira.
Nguva yekutumira: Nyamavhuvhu-04-2023